tbuckley/cabot-search huggingface dataset:
P17.16.B INVESTIGATION OF REGORAFENIB TUMOR SENSITIVITY AND UNDERLYING TREATMENT INDUCED MOLECULAR MECHANISMS IN GLIOBLASTOMA RECURRENT TUMORS
Authors: M Morelli, F Lessi, M Giacomarra, A Marranci, M Menicagli, O S Santonocito, P Aretini, F Pasqualetti, A L Di Stefano, S Franceschi, C M Mazzanti
Journal: Neuro-Oncology (2023)

Abstract BACKGROUND Glioblastoma (GB) is the most aggressive brain malignant tumor with a highly unfavorable prognosis. Maximal surgery resection, temozolomide chemotherapy (TMZ), and radiotherapy (RT), currently remain the best treatment option. Recently the phase II REGOMA clinical trial, has shown that regorafenib (REGO), a multikinase inhibitor that targets angiogenic, stromal and oncogenic tyrosine kinase receptors, significantly improves survival in GB patients.The aim of this study was to investigate Regorafenib tumor sensitivity and underlying molecular mechanisms in GB recurrent tumors leveraging on an ex vivo drug response functional precision medicine approach, that we have developed recently consisting of an in vitro vital patient-derived GB 3D organoid model and NAD(P)H Fluorescence Lifetime Imaging (FLIM). MATERIAL AND METHODS In-vitro 3D GB organoids were derived from 17 patients’ resected recurrent GB tumors. For 5 of these we had the matched primary tumor, and for other 3 we collected also the tumor peripheral portion. Totally, we obtained 25 samples. After 3 days from culture, organoids were treated with TMZ and REGO and drug response, using NAD(P)H FLIM, was assessed in the following 72 hours to stratify tumors in Sensitive (S) and Non Sensitive (NS). Whole-exome was performed on 14 tissue samples, comprising 5 primary/recurrence tumor pairs and whole-transcriptome on 11 recurrent samples before and after treatment. RESULTS Stratification of tumor cases in S and NS groups was performed both for TMZ and REGO treatment. We found 32% (n=8) and 76% (n= 19) of TMZ and REGO S tumors, respectively. Interestingly there was never a TMZ S case that was NS to REGO. Heterogeneity was found in the TMZ and REGO responsiveness for the tumor core/peripheral pair portions and in the primary/recurrence tumors pairs. It is noteworthy that all primary tumors were responsive to REGO.The drug-responsive stratification performed using our approach was also well reflected at the molecular level, as shown from transcriptome and exome RESULTS , where differently expressed genes and mutated genes were found in S versus NS tumors. CONCLUSION GB recurrent tumors resulted more responsive to REGO when compared to TMZ treatment, as expected. Thanks to our functional precision medicine approach, we were able to study the molecular alterations occurring due to the treatment, discovering biomarkers of sensitivity or resistance.
P10.05.A INDUCED SENESCENCE AND CALCIFICATION TO ANAPLASTIC MENINGIOMA
Authors: K YOKOGAMI, T Watanabe, A Mizuguchi, S Yamashita, F Matsumoto, H Takeshima
Journal: Neuro-Oncology (2023)

Abstract BACKGROUND Although the majority of meningiomas are slow-growing and benign, atypical and anaplastic meningiomas behave aggressively with a penchant for recurrence. The 5-year risk of progression for incompletely resected meningiomas is over 80 percents. Specifically, the 5-year survival rates are 78-91% and 41-65% for atypical and anaplastic meningiomas, respectively. On the other hand, it has been reported that benign meningiomas with psammoma bodies or those with bone hyperplasia at the attachment site and subtype of high calcification have a low growth rate. Here we show that BMP signals essential for bone formation, especially GREM2 upstream inhibitor of BMP signals, are involved in meningioma growth, senescence and calcification. MATERIAL AND METHODS 1) A long-term primary cultured meningioma and commercially available anaplastic meningioma (IOMM-lee and HKB-MM) are used. For immunohistochemistry and expression analysis, 87 surgical samples operated in our hospital were used.2) We observed changes in phenotype, proliferation rate and cell cycle by inhibiting BMP signal. Overexpression of GREM2, an upstream inhibitor of BMP signals, was performed in anaplastic meningiomas and analyzed comprehensively. Downloaded RNA-seq data from GREIN, a public database, and performed a comprehensive analysis of the extent of GREM2 expression and gene expression related to cellular senescence. RESULTS 1) Inhibition of BMP signaling reduced proliferation. Moreover, long term inhibition of BMP signals induced calcification. 2) Expression of GREM2 related to proliferation in surgical samples. GREM2 mainly localized surrounding of psammoma bodies. 3)Overexpression of GREM2 increased sub-G1 population and inhibits cell proliferation. 4)Expression of GREM2 shifts tryptophan catabolism from Kynurenine/NAD/NADH to serotonin production. 5) Comprehensive analysis using RNA-seq data from GREIN showed that high expression of GREM2 decreases oxidative phosphorylation. 6)Senescence assay showed that inhibition of BMP signaling induced senescence. CONCLUSION Inhibition of BMP signaling reduced proliferation and induced calcification. The underlying mechanism is shifting tryptophan catabolism from Kynurenine/NADH/NAD to serotonin production.
P06.07.B DEVELOPMENT OF A NOVEL CO-CULTURE MODEL OF GLIOBLASTOMA NEUROSPHERES WITH AUTOLOGOUS PERIPHERAL BLOOD MONONUCLEAR CELLS TO INVESTIGATE THE EFFICACY OF ONCOLYTIC ADENOVIRUS THERAPY
Authors: E Stavrakaki, W B L van den Bossche, L B Vogelezang, C Teodosio, J J M van Dongen, C M F Dirven, R K Balvers, M L Lamfers
Journal: Neuro-Oncology (2023)

Abstract BACKGROUND The dismal prognosis of glioblastoma (GBM) patients, with a median survival of less than 15 months despite maximal therapy urgently warrants new therapeutic approaches. Cancer immunotherapies such as oncolytic virotherapy have shown encouraging results against GBM, but a large fraction of patients fails to respond to treatment. As the mechanisms that malignant cells employ to avoid elimination by the immune system are diverse, we hypothesized that development of an ex vivo co-culture model that would capture the complex interactions between different immune cell types, would allow us to explore the nature and degree of immune response induced by oncolytic viruses. To this end, we established a co-culture model of primary GBM neurospheres with autologous patient peripheral blood mononuclear cells (PBMCs). MATERIAL AND METHODS Different culture parameters such as co-culture media and cell ratios were explored to select the optimal co-culture setting. Furthermore, we developed a 20-color flow cytometry panel to evaluate the phenotype of the PBMCs; markers such as CD69, HLA-DR, TIGIT on T cells, as well as M1 and M2-related signatures on monocyte-derived macrophages were assessed. Co-culture supernatants were evaluated for the presence of pro-inflammatory cytokines and chemokines. RESULTS We established that viability and effector functions of PBMCs were retained in our co-culture conditions. Co-culture of GBM cells with PBMCs induced a pro-tumoral microenvironment. However, treatment with oncolytic adenovirus led to downregulation of M2-related signatures on monocyte-derived macrophages as well as upregulation of activation markers on CD8+ T cells. We also observed increase in a number of pro-inflammatory cytokines and chemokines such as IFNγ, TNFα, CCL4 as well as granzyme b. The extent of immune activation upon treatment, however, was distinct per patient, indicating that our system may offer a tool to assess patient-specific responses to oncolytic virus treatment. Importantly, we showed that patient exposure to dexamethasone prior to PBMC isolation did not preclude the IFNγ production in our system. CONCLUSION We established an autologous GBM/PBMCs co-culture model which reflects inter-tumoral heterogeneity in response to oncolytic virotherapy. This may allow the establishment of an ex vivo assay to assess and predict individual patient response to oncolytic virotherapy and possibly in the future also to other immunotherapies.
P22.01.A PERSON-CENTRED PRACTICE: EXPLORING FAMILY STRENGTH BY USING GENOGRAMS AND ECOMAPS
Authors: M Mathiasen, S Suhr Kjærgaard, K Piil
Journal: Neuro-Oncology (2023)

Abstract BACKGROUND Illness of a family member impacts the entire family. Family relationships, roles and tasks often change, and neuro-oncological caregivers experience a high level of burden and distress when playing a vital role in the informal care of the patient. The theory of Family Systems Nursing advises to approach the family rather than merely the patient. Within Family System Nursing the Family Nursing Conversations is an important intervention that focus on the interactions within a family and between the nurse and the family. The Calgary Family Assessment and Intervention Model (CFAM/CFIM) guide clinical practice to be family focused. According to these models, the drawings of genograms and ecomaps are efficient tools to graphicly portray the specific family constellation and social relationships. This presentation shows how genograms and ecograms can be applied to strength the dialogue with a family when implementing family-focused conversations. MATERIAL AND Methods In the neuro-oncological outpatient clinic at the University Hospital of Copenhagen we offer family and/or caregiver conversations. At the initial conversation, a genogram and an ecogram are drawn. By visualizing the family structure and interrelationships, the family is illustrated as a unit and the family can see their constellation in relation to each other and to the outside world. RESULTS Based upon the genograms and ecograms, a dialogue takes place. They have shown to be important tools to visualize the structure, with strengths and challenges within a family system. Further, they provide a good starting point for a family-focused communication. However, to implement these tools, training is required. Therefore, we have prepared teaching material to healthcare professionals. This material has been tested in family-focused conversations. CONCLUSION The use of genograms and ecomaps have proven to be efficient for a family-focused approach in a neuro-oncological outpatient clinic. They facilitate a good starting point for a family to identify their relationships and resources. During the conversations the family/caregivers often gain new insights and management strategies for coping.
P02.04.B TARGETING METABOLIC VULNERABILITIES IN GLIOBLASTOMA
Authors: A Burban, A Sharanek, A Bikfalvi, T Daubon
Journal: Neuro-Oncology (2023)

Abstract BACKGROUND Glioblastoma is the most common and aggressive primary brain cancer, with a median survival of 16 months. A subset of cells within these tumours, termed glioblastoma stem cells (GSCs), displays high tumourigenic capacity and resistance to conventional therapies, and are responsible for tumour recurrence. Glioblastomas have been initially shown to mainly rely on glycolysis as a source of energy. However, a growing body of literature reports that GSCs are less glycolytic than their differentiated progeny and can thrive on oxidative phosphorylation (OXPHOS) to survive, sustain stemness and fuel tumourigenic potential. Thus, targeting OXPHOS could be a promising strategy to halt energy production and starve GSCs to death. However, under metabolic stress, GSCs can also switch to a more glycolytic phenotype, suggesting a metabolic plasticity in GSCs, and thus adding a layer of complexity to target GSC metabolism. In the current study, we have investigated the impact of compound X (CX), recently shown to impair mitochondrial respiration, on the fate and tumourigenesis of GSCs. MATERIAL AND METHODS Multiple patient-derived and murine GSC models were used to test the impact of CX on GSCs in vitro. The effect of CX on glioblastoma tumors was evaluated using patient-derived xenografts and syngeneic mouse models. RESULTS We have established that CX inhibits GSC proliferation and impairs stemness-related pathways in vitro. CX delays glioblastoma tumourigenesis in vivo. While a drastic decrease in cell proliferation was observed, cell death assays revealed that CX does not induce cell death. This suggests that GSCs gain a slow-cycling phenotype to resist energy depletion. Mechanistically, we have established that CX targets complex I of the mitochondrial respiratory chain, leading to an impairment of OXPHOS. Interestingly, inhibition of OXPHOS by CX was associated with an extensive production of extracellular lactate, indicating that at least, a subset of GSCs gain metabolic adaptability by co-opting glycolysis to survive. Thus, to tackle this metabolic plasticity in GSCs, we adopted a new strategy that involves sequestration of the lactic acid intracellularly via disruption of lactate transporters. Treatment of GSCs with monocarboxylate transporter inhibitors, AZD3965 and syrosingopine, alone did not significantly impact GSC growth and viability. Strikingly, combined CX treatment with either AZD3965 or syrosingopine resulted in high intracellular lactate buildup, increased reactive oxygen species, and led to drastic cell lethality in multiple GSC models. CONCLUSION This study highlights that re-routing the OXPHOS-dependent GSCs to glycolysis offers a vulnerability to sensitize GSCs to cell death. Dual inhibition of OXPHOS and lactate export could be a promising therapeutic approach to deplete malignant GSCs and suppress glioblastoma tumourigenesis.
P17.01.A THE VALUE OF ETOPOSIDE FOR RECURRENT GLIOMA
Authors: M van der Meulen, M Chahal, W P Mason
Journal: Neuro-Oncology (2023)

Abstract BACKGROUND There is currently no consensus on how best to treat diffuse glioma in adults at recurrence. Etoposide in combination with carboplatin and/or bevacizumab has been evaluated in recurrent glioma with modest efficacy. This retrospective study investigates the efficacy of etoposide monotherapy in adults with recurrent diffuse glioma. MATERIAL AND METHODS In this single center retrospective series, all adult patients with radiographically proven multiply recurrent diffuse glioma (WHO grade 2-4) treated with etoposide between 2016 and 2020 were evaluated. Progression-free survival (PFS) and overall survival (OS) after initiating etoposide were calculated for the total group and for different histologic tumor types. In addition, toxicity was recorded after initiation of etoposide. RESULTS 48 patients with a median age 43 (range 24-78) were included. Etoposide was given as 3rd line of treatment in 18 patients (37.5%) and as 4th or 5th line of treatment in 30 patients (62.5%). The majority were diagnosed with a glioblastoma, WHO grade 4 (27, 56.3%). The median PFS was 8.6 weeks (95% confidence interval [CI]: 8.3-8.9). The median OS of the total population was 4.0 months (95% CI: 2.4-5.6). Patients with an oligodendroglioma had the best OS (median 13 months), compared to astrocytoma and glioblastoma, but the difference was not statistically significant (p=0.152). Etoposide was stopped due to progression or toxicity. Only 1 patient had a grade 3 toxicity. CONCLUSION Etoposide is a well-tolerated chemotherapy in adult patients with recurrent diffuse glioma, but has limited efficacy in this cohort of multiply recurrent and heavily pretreated patients.
P04.04.A GENOME-WIDE CRISPR/CAS9 KNOCKOUT SCREENS REVEAL EPIGENETIC REGULATORS AS DRUGGABLE TARGETS FOR SONIC HEDGEHOG MEDULLOBLASTOMA
Authors: F Tsiami, F Piccioni, D Root, P Bandopadhayhay, R Segal, G Tabatabai, D Merk
Journal: Neuro-Oncology (2023)

Abstract BACKGROUND Sonic hedgehog medulloblastoma (SHH-MB) is a malignant pediatric brain tumor that accounts for 30% of all MBs and is characterized by constitutive activation of the SHH signaling pathway. Besides the standard-of-care therapies, current therapies are targeting Smoothened (SMO) receptor, in order to inhibit the pathway. However, acquired or de novo resistance against SMO inhibition limits its efficacy. Therefore, our aim is to unravel novel therapeutic targets for SHH-MB, potentially beyond the SHH pathway. MATERIAL AND METHODS We performed genome-wide CRISPR/Cas9 knockout screens, in order to decipher cancer dependencies and synthetic lethal interactors for SHH-MB. The hits identified were first validated genetically and pharmacologically in in vitro assays, while further molecular analyses including RNAseq and differential methylation were also conducted. Moreover, the identified hits were evaluated in in vivo mouse models representing normal cerebellar, as well as SHH-MB development. RESULTS Functional genomics identified members of the epigenetic machinery, such as Dnmt1 and Smarca5 as context-specific dependencies for SHH-MB. We prove that DNMT1 inhibition is efficacious against SMO-resistant and sensitive SHH-MB cell lines, by inhibiting SHH pathway output, as shown via RNAseq. A further knockout drug screen unraveled novel synthetic lethal interactors for DNMT1 inhibitors. Genetic ablation and pharmacological inhibition of epigenetic regulators prolongs survival of established mouse models of SHH-MB. CONCLUSION Summarizing, our data indicate inhibitors of epigenetic regulators as novel therapeutic targets for SHH-MB irrespective of mutational drivers within the SHH pathway. We further propose combinatorial treatment approaches for this tumor entity that involve DNMT1 inhibitors.
P22.03.A FEASIBILITY OF AND COMPLIANCE TO ELECTRONIC PATIENT-REPORTED OUTCOME ASSESSMENT IN THE MOLECULAR TUMOR BOARD IN (NEURO-)ONCOLOGICAL PATIENTS UNDER TARGETED THERAPY (TRACE)
Authors: M Renovanz, F Stange, L Dörner, P Bombach, L Grosse, J Rieger, M Skardelly, D Rieger, H Hille, S Kurz, M Hippler, F Paulsen, Ö Öner, K Ruhm, J Beha, H Sundberg Malek, Y Möller, M Tatagiba, M Wallwiener, P Escher, N Pfeiffer, A Forschner, A Bauer, D Zips, M Bitzer, N Malek, C Gani, G Tabatabai
Journal: Neuro-Oncology (2023)

Abstract BACKGROUND Comprehensive genomic profiling and biomarker-based therapies are increasingly used in clinical trials and in innovative health care systems including the center for personalized medicine network. Systematic assessments of patient-reported outcomes (PRO) are warranted to gain insight into the perspective of patients during biomarker-based therapies. In the present study, we focused on the feasibility of and compliance to an electronic PRO assessment in patients treated at our center. MATERIAL AND METHODS Based on a retrospective evaluation of symptom burden in 265 neurooncology patients in the Molecular Tumor Board (MTB), we developed an app by 14 expert rounds including validated assessments of health-related quality of life (HRQoL), burden of symptoms und psychological stress, and tested it in a pilot study. After informed consent, patients were introduced to the app by study staff and completed subsequently patient-reported outcomes at several time points (weekly, monthly, and quarterly). We conducted a structured interview with health care personnel and the patients as users after 3 months to assess the app’s usability and feasibility. The interview was transcribed and analyzed according to Mayring´s qualitative content analysis regarding handling, feasibility and applicability in daily routine.Furthermore, we assessed compliance and descriptive data of the ePROs. RESULTS So far, 14 patients and caregivers have been enrolled, (9 female, 5 male). Median age was 50 years (range 28 -79), 3 out of 14 patients dropped out due to death. A total of 4 study staff members, 9 patients and one caregiver were interviewed regarding usability /feasibility. Both evaluated as good (study staff members in total n=40 quotes, patients/caregivers n=112 quotes). Main advantages were the possibility to complete questionnaires at home and the easy implementation in daily life. Compliance to questionnaires was high, e.g., 91% of weekly distributed NCCN Distress Thermometer were answered in time (range 65-100%, assessment duration 5-56 weeks, 262 answers), we observed a median Distress score of 4 (range 0-9, n=262, weekly assessed) and a median Global health score of 66.7 (range 16.7-100, n=69, EORTC QLQ-C30, question 29 and 30, monthly assessed, compliance 94%). CONCLUSION This pilot study proved feasibility and acceptance of the app and might enable PRO assessment during biomarker-guided therapies.
P14.03.A DO GLIOMA PATIENTS PRODUCE AUTO-ANTIBODIES FOR GLIOMA-SPECIFIC PHOSPHO-PROTEIN MODIFICATIONS
Authors: L Zeneyedpour, C Stingl, J M Kros, P A E Sillevis Smitt, T M Luider
Journal: Neuro-Oncology (2023)

Abstract BACKGROUND Many studies have shown that dysregulation of protein phosphorylation plays an important role in the development of cancer. Aberrantly phosphorylated peptides can be derived from dysregulated cell signaling pathways in various cancers and may serve as tumor-specific antigens and might be promising targets for cancer immunotherapy. Several techniques are available to purify immunoglobulins (IgG) from plasma or other body fluids using affinity to immobilized binders In contrast, Melon Gel resin retains non-IgG proteins and hence allows enrichment of IgG directly from the sample without affinity binding. We have developed a technique for the detection of auto-antibodies in HGG. MATERIAL AND METHODS To perform an Ab-peptide binding assay, we used a phospho-peptide library (a mixture of phospho-peptides obtained after phospho-enrichment of enzymatically digested fresh-frozen GBM tissue) and three plasma samples from HGG patients and a healthy donor as source of IgG. After mixing of the plasma samples with the phospho-peptide library the IgG purification was performed using the Melon Gel resin. We separated possible unbound peptides using a 30 kDa-molecular-weight (MW) filter device. The high MW fraction, containing IgGs and IgG-peptide complexes were acidified and precipitated to release Ab-bound peptides. Subsequently, the IgG-bound peptides were measured and identified in a mass spectrometer. RESULTS Performing the developed Ab-peptide binding assay using the HGG and healthy plasma samples combined with the GBM phospho-peptide library, we detected EGFR phospho-peptide GSHQIS[+80]LDNPDYQQDFFPK (S1166) in three of four IgG-bound fractions of samples incubated with HGG plasma and not in the corresponding unbound fractions. This result indicates the presence of auto-antibodies against EGFR phospho-peptide S1166 in the plasma of the three HGG patients. A contrasting result was obtained in the donor sample, where the EGFR peptide was detected almost exclusively in the unbound fraction. With the use of Avastin as negative control instead of plasma, the EGFR peptide S1166 was solely found in the unbound fraction. CONCLUSION An antibody-peptide-antigen complex enrichment with Melon Gel was successfully applied to find auto-antibodies that recognize disease-related phospho-peptides. This method has the potential to detect the putative presence of auto-antibodies without knowledge of the antigen. We demonstrated in a proof of concept the presence of auto-antibodies against an EGFR phospho-peptide in plasma of HGG patients. This antibody-peptide binding assay could potentially be further applied to other types of cancer to find targets for therapeutic interventions.